Fuel injection device



July 25, 1961 J. H. BREADY 2,993,486

FUEL INJECTION DEVICE Filed March 20, 1959 2 Sheets-Sheet 1 78 74 FIG. 1.

l2 o w Z fier. u e o (62 j; XAW. L-

Sww 94 E 2 i. sM51 a L;

F/ G. 3. xNvEN'roR.

JOHN H. efy,

www +2) 47706? EVS United States Patent Oiiice 2,993,486 Patented July 25, 1961 2,993,486 FUEL INJECTION DEVICE John H. Bready, Takoma Park, Md. (13117 Lutes Lane, Silver Spring, Md.) Filed Mar. 20, 1959, Ser. No. 800,800 6 Claims. (Cl. 123-139) The present invention relates to a fuel injection device for an internal combustion engine.

Presently in use and previously proposed lare fuel injection devices for internal combustion engines. Such devices each include a means for adjusting the volume of the charge of liquid fuel :admitted at each power stroke of the engine piston. Generally, the fuel volume adjusting mechanism of such a device is of complex and intricate construction usually 'requiring machining of many parts to extremely close tolerances. The initial expense of machining the parts of such a fuel injector is considerable and the maintaining of the parts at the required tolerances entails further expense. The advantages of fuel injection devices over conventional carburetor systems are often offset by the ladditional cost of installation and maintenance of the fuel injection devices.

An object of the present invention is to provide a fuel injection device which lends itself to economical manufacture, installation, and maintenance, in an internal cornbustion engine and one which requires a minimum of machining to close tolerances of its component parts.

Another object of the present invention is to provide a fuel injection device for an internal combustion engine which is simple in structure, one sturdily constructed and having a few moving parts, one which is positive in opera.- tion, and one highly effective in action.

These and other objects and advantages of the present invention will be fully `apparent from the following description when taken in conjunction with the annexed drawings, in which:

FIGURE 1 is a sectional view of an internal combustion engine with the fuel injection device of the present invention installed thereon, the electrical circuit of the invention being shown schematically;

FIGURE 2 is a view taken on the line 2 2 of FIG- URE 1, the dotted line showings indicating other fuel injection devices for a multiple cylinder internal combustion engine;

FIGURE 3 is a view on an enlarged scale, taken on the line 3 3 of FIGURE l;

FIGURE 4 is a sectional view on an enlarged scale, taken on the line 4 4 of FIGURE 2; and

FIGURE 5 is a view taken on the line 5 5 of FIG- URE 4.

Referring in greater detail'to the drawings in which like numerals indicate like parts throughout the several views, in FIGURE 1, the reference numeral designates generally an internal combustion engine including a rotatable cam shaft 12 and a cam 14 carried by the shaft 12. A piston 16 is reciprocally mounted within the engine 10 and is driven therein in response to the eX- plosive forces of gases in the combustion chamber 18 of the engine l10 in the conventional manner. One or more valves 20 control the intake and exhausting of combustion air and combustion products from the chamber 18, the valves 20 being operable by other cams on the shaft 12, also in the conventional manner.

The fuel injection device of the present invention is designated generally by the reference numeral 22 and comprises a housing having therein a fuel supply chamber 24.

A conduit 26, constituting fuel supply means, is eX- teriorly of the chamber 24 and connects the chamber 24 in communication with a source of liquid fuel under pressure.

The housing of the device 22 is provided with a fuel conveying passageway 28 Iadjacent the fuel supply chamber 24.

A rst means is movably mounted in the passageway 28 for controlling the flow of liquid fuel from the chamber 24 into the passageway 28. This means consists in a piston or plunger 30 -reciprocally mounted within the passageway 28. A portion of the plunger 30 projects exteriorly of the housing of the device 22 and is connected by a link member 32 to an intermediate portion of a lever 34.

The plunger 30 is provided with an inlet passage having one end connecting in communication with the chamber 24 and the other end connecting in communication with the passageway 28. A check Valve 36 in the inlet passage 38 controls the flow of fuel in the passage 38.

The plunger 30 is provided with a Valve seat 40 against which the check valve 36, in the form of a ball, seats in response to an increase in pressure in the passageway 28 or the pressure in the inlet passage 38.

The nlink member 32 constitutes means connecting the plunger 30 to the lever 34 for movement with the latter. One end of the lever 34 rides on the cam 14 and the other end of the lever 34 is supported in a toggle link 42.

A second means is movably mounted within the passageway 28 and spaced from the plunger 30 for discharging fuel from the passageway 28. This means constitutes a second plunger 44 reciprocably mounted within the passageway 28 for movement toward and away from the plunger 30.

The plunger 44 is provided with a discharge passage 46 and a valve seat 48 against which abuts a ball 50 constituting a check valve whenever the pressure within the passage 46 is in excess to the pressure within the passageway 28.

A flexible conduit 52 has one end connected -in communication with the end of the passage 46 remote from the ball 50, the other end of the conduit 52 being connected in communication with an injector housing 54.

The injector housing 54 has a portion 56 adjacent one end threaded and threadedly received within a threaded bore provided in the engine 10. A sleeve 58 is positioned within the portion of the housing 54 inwardly of the portion 56 and is provided with a restricted orice 60 in which is normally seated -a needle valve 62. The needle valve 62 is biased to seating engagement in the orice 60 by means of a compression spring 64 having one end bearing against the shoulder 66 provided on the valve 62 and the other end bearing against a disc 68 movable on the end of |a screw 70 which projects into the end of the housing 54 remote from the threaded portion 56.

A spark plug 72 projects into the housing 54 and sleeve 58 and is in a position to ignite fuel ejected through the orifice 60.

A conduit 74 has one end connected in communication with the portion of the housing 54 between the orifice 60 and the shoulder 66 and the other end connected in communication with the free end of the conduit 52.

A knob 76 on the end of the screw 70 permits the screw 70 to be manually adjusted into and out of the housing 54 so as to vary the pressure of the spring 64 on the shoulder 66.

The terminal of the spark plug 72 is connected by a Wire 78 to the high tension side of a spark producing coil assembly 80, of conventional construction, and of the vibrator type. A battery 82, having one side grounded on the engine 10, has its other side connected to the coil assembly 80. A fixed contact 84 Vis carried on the device 22 and is electrically connected with the coil assembly 80. A movable contact 86 is mounted on the lever 34 for movement into and out of engagement with the contact 84 in response to rotation of the shaft 12.

A coil spring 88 has one end connected to the lever 34 at a point intermediate the contact 86 and the free end of the lever 34. The other end of the coil spring 88 is secured to a pin 90 which projects from one side of the housing of the device 22. The spring 88 urges the lever 34 for rocking movement in the clockwise direction when released from the cam 14 on the shaft 12.

A shaft 92 is positioned below and exteriorly of the device 22 and carries a cam 94 thereon. The cam 94 is in engagement with a roller 96 rotatably supported on the lower end of the plunger 44. A hand actuable lever 98 is operatively connected by a link 100 and an arm 102 to the shaft 92 for eecting the rotation of the latter. One end of the lever 98 is connected by a pin 104 to the housing of the device 22.

As it will be shown most clearly in FIGURE 4, upward movement of the free end of the lever 98 will raise the plunger 44 toward the plunger 30.

Means is provided for the timing sequence of the firing of the spark plug 72 in order to advance or retard the action of the engine 10. This means consists of a lever 166 having one end pivotally mounted on the housing of the device 22 and having an intermediate portion connected by a link 108 to the free end of the toggle link 42. The shifting of the lever 106 upwardly alters the position of the free end of the lever 34 relative to the came 14 so that the cam 14 releases the lever 34 earlier or later, depending upon the direction of rotation of the shaft 12. This results in closing of the contacts 84 and 86 together at a predetermined instant relative to the injection of fuel through the conduit 52, 74, and through the orilce 60 into the sleeve 58 for ignition by the spark plug 72.

The strength of the spring 64 is adjusted by the knob 76 so as to maintain fuel under a high pressure within the housing S4 between the shoulder 66 and the orifice 60, such pressure being generated by the reciprocal motion of the plunger 30 toward and away from the plunger 44.

In use, the device 22 is secured to the engine 10 by suitable bracket means, not shown, and the conduit 26 connected to a source of fuel under pressure. As the shaft 12 rotates, the cain 14 raises the free end of the lever 34 to lift the plunger 30. This results in seating of the ball 50 on the valve seat 48 and a reduction of the pressure in the passageway 28. Fuel is drawn from the chamber 24 through the inlet passage 38 into the passageway 28, unseating the check valve 36 from the valve seat 40. Upon rotation of the shaft 12 to the position in which the cam 14 no longer engages the lever 34, the spring 88 exerts a pulling force on the lever 34 to depress the plunger 30, driving the fuel from the passageway 28 through the plunger 44 into the conduit 52 and conduit 74 and thence into the housing 54 and orifice 60 at such a pressure as to unseat, by its pressure on the shoulder 66, the needle valve 62 from the orifice 60.

Manual movement of the lever 98 upwardly shifts the plunger 44 into engagement with the plunger 30, thereby preventing movement of the plunger 30 under the urging of the spring 88 and cutting off ow of fuel to the engine 10.

Shifting of the lever 106 upwardly and downwardly moves the lever 34 longitudinally so that its free end is engaged by and released from the cam 14 at different points relative to the rotary movement of the cam 14. This advances or retards the injection of fuel to the cylinder relative to movement of the piston into and out of the top dead center position.

What is claimed is:

1. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means eX- teriorly of said supply chamber and connected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, a rst means movably mounted in said passageway for controlling the flow of fuel from said supply chamber into said passageway, means connecting said lirst means to said to said cam for movement with the latter, a second means movably mounted within said passageway and spaced from said rst means for discharging fuel from said passageway, means connected to said second means for moving and selectively positioning said second means toward and away from said first means, and means connecting said second means to said combustion chamber.

2. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means exteriorly of said supply chamber and connected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, a first means movably mounted in said passageway for controlling the ow of fuel from said supply chamber into said passageway, said iirst means embodying a first plunger provided with an inlet pasage having one end opening in communication with said supply chamber and having the other end controlled by a check valve, means connecting said first means to said cam for movement with the latter, a second movably mounted within said passageway and spaced from said first means for discharging fuel from said passageway, means connected to said second means for moving and selectively positioning said second means toward and away from said rst means, said second means embodying a second plunger provided with a discharge passage having one end opening in communication'with said passageway with a check valve controlling said opening and having the other end opening out of said second plunger, and conduit means connecting the other end of the discharge passage of said second plunger in communication with said combustion chamber.

3. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means exteriorly of said supply chamber and connected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, a firs-t means movably mounted in said passageway for controlling the ow of fuel from said supply chamber into said passageway, said rst means embodying a first plunger provided with an inlet passage having one end opening in communication with said supply chamber and having the other end controlled by a check valve, a lever disposed exteriorly of and having one end pivotally mounted on said chamber and having the other end drivably engaging said cam for rocking movement in one direction responsive to rotation of said shaft, spring means operatively connected to said lever urging the latter in the opposite direction, means connecting said first plunger to said lever for movement therewith, a second means movably mounted within said passageway and spaced from said first means for discharging fuel `from said passageway, means connected to said second means for moving and selectively positioning said second means toward and away from said first means, and means connecting said second means in communication with said combustion chamber.

4. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means exteriorly of said supply chamber and connected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, a rst means movably mounted in said passageway for controlling the flow of fuel from said supply chamberinto said passageway, means connecting said lirst means to said cam for movement with the latter, a second means movably mounted Within said passageway and spaced from said rst means for discharging fuel Ifrom said passageway, said second means embodying a plunger provided with a discharge passage having one end opening in communication with said passageway with a check valve controlling said opening and having the other end opening out of said plunger, a second rotatable shaft, a cam on said second shaft, means connecting said plunger to the lastmentioned cam for moving said plunger toward and away from said iirst means responsive to rotation of said second shaft, manually operable means operatively connected to said second shaft for moving and selectively positioning said plunger, and conduit means connecting the other end of said discharge passage of said plunger in communication with said combustion chamber.

5. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means exteriorly of said supply chamber andconnected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, -a rst means movably mounted in said passageway for controlling the flow of fuel from said supply chamber into said passageway, said first means embodying a first plunger provided with an inlet passage having one end opening in communication with said supply chamber and having the other end controlled by a check valve, a lever disposed exteriorly of and having one end pivotally mounted on said chamber and having the other end drivably engaging said cam for rocking movement in one direction responsive to rotation of said shaft, spring means operatively connected to said lever urging the latter in the opposite direction, means connecting said iirst plunger to said lever for movement therewith, a second means movably mounted within said passageway and spaced lfrom said first means for discharging fuel from said passageway, said second means embodying a second plunger provided with a discharge passage having one end opening in communication with said passageway with a check valve controlling said opening and having the other end opening out of said second plunger, a second rotatable shaft, a cam on said second shaft, means connecting said second plunger to the lastmentioned cam for moving said second plunger toward and away from said first plunger responsive to rotation of said second shaft, manually operable means operatively connected to said second shaft for moving and select-ively positioning said second plunger, and conduit means connecting the other end of the discharge passage of said second plunger in communication with said combustion chamber.

6. The combination with an internal combustion engine including a rotatable shaft, a cam carried by said shaft, and a combustion chamber, of a fuel injection device comprising a fuel supply chamber, fuel supply means ex- Iteriorly of said supply chamber and connected in communication with said supply chamber, a fuel conveying passageway adjacent said supply chamber, a rst means movably mounted -in said passageway for controlling the ilow of fuel from said supply chamber into said passageway, said first means being provided with an inlet passage having one end opening in communication with said supply chamber and having the other end controlled by a check valve, means connecting said rst means to said cam for movement with the latter, a second means movably mounted within said passageway and spaced from said first means Afor discharging fuel from said passage way, means connected to said second means for moving and selectively positioning said second means toward and away from said first means, said second means being provided with a discharge passage having one end opening -in communication With said pasageway with a check valve controlling said opening and having the other end opening out of said means, and conduit means connecting the other end of the discharge passage of said second means to said combustion chamber.

References Cited in the file of this patent UNITED STATES PATENTS 2,195,037 Petty Mar. 26, 1940 FOREIGN PATENTS 361,970 Great Britain Nov. 30, 1931 

